abstract
Increasing cement production in construction sector and waste generation in industrial sectors are of the major sources of CO2 emission. For decades, it has been the concern of environmentalists to convince constructors and researchers to find sustainable solutions targeting aforementioned problems. The attempts focused on identification of wastes to be successfully complied with construction materials. Biochar has recently received attention due to several environmental and technological advantages, shortly include carbon sequestration, low thermal conductivity, chemical stability and low flammability. For this reason, biochar is recognized as an efficient candidate for cement or lightweight aggregates replacement in building materials. Biochar addition could result in a reduction of capillary absorption in mortar paste. Besides, its addition accelerates cement hydration and restricts shrinkage cracking in cement mortar. The present review categorizes all the biochar critical features affecting the performance of cementitious materials. The effect of biochar addition as filler and cement replacement on the workability, hydration, mechanical and transfer properties of cement paste/composites is reviewed in this paper. From the data collection, an optimum biochar content around 2% is shown to contribute to the improvement of mechanical properties. The gaps in the literature are identified and the future research plans are proposed. (C) 2021 Published by Elsevier Ltd.
keywords
RUBBER-WOOD-SAWDUST; INTERNAL RELATIVE-HUMIDITY; TRANSITION ZONE ITZ; PYROLYSIS TEMPERATURE; CHEMICAL-COMPOSITION; BUILDING-MATERIALS; SLOW PYROLYSIS; SEWAGE-SLUDGE; PARTICLE-SIZE; BLACK CARBON
subject category
Construction & Building Technology; Engineering, Civil; Materials Science, Multidisciplinary
authors
Maljaee, H; Madadi, R; Paiva, H; Tarelho, L; Ferreira, VM
our authors
acknowledgements
The authors would like to acknowledge the support of the H2020 EU Research and Innovation programme for the funding of the Paperchain project under grant agreement no 730305. Thanks are due to the Portuguese Foundation for Science and Technology (FCT)/Ministry of Science, Technology and Higher Education (MCTES) for the financial support to CESAM (UIDP/50017/2020+UIDB/50017/2020), through national funds.